Cooling system



J. H. HUNT COOLING SY STEM June 18, 1929.

Filed June 13, 1927 Patented June 18, 1929.

UNITED STATES 1.717,;689 PATENT OFFICE.

JOHN H. HUNT, OF DETROIT, MICHIGAN, ASSIGNOR T0 GIA'IERAL MOTORS RESEARCH CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION 0F DELAWARE.

COOLING Application led I une 13,

This invention relates to cooling systems for internal combustion engines of the type employed to propel motor vehicles, and has for one ot' its objects, the provision of an improved type of radiator to extract heat from the cooling medium and which will eifeetu ally condense all vapors, thereby preventing loss or escape of the cooling liquld and thru the radiator, shown in Fig. 1, and Figure 3 is a transverse section thru a radiator formin a part of a hot water system.

leferring first to the steam cooling system illustrated in Figures 1 and 2, the reference numeral 1 indicates an explosive engine, which embodies the customary water jacket or cooling chambers, and the numeral 2 refers to a radiator or condenser. The radiator 2 is shown as of the cross flow type, wherein a series of transverse tubes 3, provided with cooling fins, connect a vertically disposed inlet chamber 4 with an outlet chamber 5. A pressure pump 6, driven off the engine crankshaft in any suitable manner, withdraws cooling medium, which is generally water or a solution of water and alcohol, or other nonfreezing Huid, from the bott/om of the radiator, and forces or delivers the cooling liquid thru the conduit or pipe 7 to the interior of the water jacket or cooling chambers of the engine. The cooling medium in absorbing heat of combustion, vaporizes and the hot steam vapors leave the cooling jacket to enter the chamber 4, thru the inlet port or opening 8 in the top thereof. In Figure 2, the' general direction of the flow of vapors is indicated by darts. As the heat is dispelled in the passage of the vapors thru the transverse tubes 3, the gases condense and fallto the bottom of the radiator for recirculation.

During Some conditions of use, it is found that a small part of the vapors are not condensed by their passage thru the tubes, and upon reaching the outlet chamber 5, there is a tendency for these gases to leave the cooling system thru the customary air vent, which necessitates the addition from time to time SYSTEM.

1927. Serial No. 198,501.

of more liquid. This loss increases with the use of anti-freeze solutions of low vboiling point, and the necessary replenishment, be-

longer rushing past the fins to take up the heat, a small amount of steam is boiled out of the system.

To meet the situation, it is proposed to provide an auxiliary condenser to augment the usual radiator, which may be in the form of a liquid trap or seal in the top of the radiator and in advance of the air vent, to condense the steam or vapors and prevent their escape to atl. mosphere. In the present instance, this tran is formed by a partition wall 10, providing a chamber 11 in the upper part of the radiator and whichhasanupstandingspoutorovertlow pipe 12 establishing communication between opposite sides of the wall 10.- v A bell or cap 13 ispositioned over the overflow spout 12 to ati'ord the seal or trap, the sidesof whichexvtend sufficiently below the li uid level that surging of the liquid will not reak the seal. The trap is preferably located in the center of the partition 10, where the overflow of liquid is least affected by inclination of the liquid level to one side or another, due to tilting of the radiator when vthe motor vehicle is traveling on a slanting roadway, and for the further 'r'eason that they bell or cap 13 may be carried by a dependent stem 14 on the removable filler cap 15, to facilitate the admission of cooling medium to the radiator thru the ller spout 16. The wall 10 is spaced above the top oi' the assembly of cross flow tubes 3, to afford a chamber 17 communicating at one side with the vertical outlet chamber 5. Pressure of air within the cooling system due to heat eX- y pansion, is relieved thru the customary vent opening 19, as the air bubbles thru the liquid trap. The vapors of the cooling fluid, however, are condensed when' they attempt to pass the trap, and are thus prevented from escape..

A by-pass 20 leads fromr the delivery side of the pump 6 upwardly and enters the chamber 11 at 21. To insure suiiicient pump pres-- sure, especially at low speeds, to lift the liquid thru the by-p'ass 20, a restriction such as the perforated disc 22, may be placed in the supply pipe. 7 or in lieu t ereof, a valve held on its seat by a comparatively weak sprmg-may be employed to build up the necessary pressure.

Th provision of the by-pass is an important feature of the present invention, since it.

suppliesa continuous flow of cooled liquid to the trap, which may then overflow thru the spout 12 and return to the bottom of the radiator carrying along the entrapped condensate. Thus the liquld in the trap is being 'constantly changed, eliminating any pssibility (if the freezing point of the liquidin the radiator being raised to a dangerous amount by the concentration of the anti-freeze portion of the solution inthe trap, with the recooling jacket, and serving as an inlet chamber for the hot fluid. The heatof the liquid is dispelled in the usual manner by its passage thru the main radiator portion 25, and the liquid entering the outlet chamber 28 at the bottom of the core assembly is sent back into the engine jacket by the pump 29.- From v the delivery side of the pump 29 a b -pass conduit .30 leads upwardly to a cham `r 31 at the top of the radiator, and a small portion of the fluid supply which has passed thru the main radiator, constantly flows thru the upper portion 26 and is further cooled. Any vapors set free at the inlet chamber 27 would tend to pass upward to atmosphere thru the auxiliary radiator portion 26, where they would be again condensed and entrapped with the iuid flowing therethru, whose temperature has been considerablyreduced below that of the fluid leaving the engine.

While the invention has been described more or less specifically it is to be understood that there is no intention to limit the invention to the exact details but that such obvious modifications may be made as come within the scope of the appended claims.

Having described my invention, I claim:

1. A cooling system for internal combustion engines, including a main condenser for cooling vapor, an auxiliary condenser adapted to supplement said main condenser, and means to withdraw condensed liquid from the main condenser for circulation thru the engine and a by-pass for directing a portion of said condensed liquid through the auxiliary condenser. 2. A cooling system for internal combustion engines, includin a radiating unit, a chamber associated t erewith having an opening to atmosphere, a fluid trap interposed between the openingand radiator, and means to withdraw coledV Huid from the radiator and deliver a portion to said trap.

3. A cooling system for internal combustion engines including in combination, an internal combustion engine having chambers for cooling liquid, a radiator, a liquid trap closing the radiatorfrom atmfosphcre, a pressure pump adapted to deliver cooled liquid from the radiator to the engine, and a byepass to supply a portion of such liquid to the liquid tra 4I.) A cooling system for internal combustion engines, including a heat radiating unit, an outlet chamber for cooled liquid, means to vent the system, a condenser associated with said ventand means to'withdraw cooled liquid from said chamber and direct aportion of it j through said condenser.

y5.l A cooling system for internal combustion engines, including a nain circulating system having therein a heat radiating unit, means to vent said system, a liquid trap associated with saidmeans, andan auxiliary cir- ,culating system adapted to receive a'portion of the liquid-in the main system after passage throu h the radiating unit for passage throu h Vsaid trap.

' 6. cooling system for internal combus. tion en es, including a heat radiating unit,

a cham er for Huid that has passed'through I said unit, a vent to Aatmosphere in said system, a condenser associated with said vent for condensing the vapors'that tend to leave the system through said vent, and means to flow the cooled fluid from said chamber through said condenser. v

7. A cooling system foiinternal combustion engines,.including a heat radiating unit, an outlet chamber for cooled liquid, a liquid trap closingA the chamber from an opening to atmosphere and means to withdrawcooled liquid from said chamber and direct a portion thereof to said trap, whence it returns to said chamber.

8. The combination with an engine having a water jacket and a heat radiating unit form ing a part of a system for circulating cooling liquid through said jacket, of a liquid trap closing the system to atmosphere, and means to by-pass cooled liquid that has passed through the radiating unit from the engine jacket, for introductioninto said liquid trap.

In testimony whereof I ailix my signature. 

